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<b><i><font face="Arial">Merge Control</font></i></b>
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<p><font face="Arial Black"><font size=-1>Purpose</font></font>
<ul><b>Merge Control</b> affects the behavior of overlapping objects. If
it is set, the <b>Merge Control</b> opcode signifies to the viewer that,
a raster op has to be performed on drawables in order to merge objects,
whenever the drawables overlap.</ul>
<font face="Arial Black"><font size=-1>Syntax</font></font>
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<td VALIGN=TOP WIDTH="19%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode
format</font></font></font></td>

<td VALIGN=TOP WIDTH="20%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode</font></font></font></td>

<td VALIGN=TOP WIDTH="30%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Operand
Format</font></font></font></td>

<td VALIGN=TOP WIDTH="31%" HEIGHT="26" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Comments</font></font></font></td>
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<td VALIGN=TOP WIDTH="19%"><font face="Arial"><font size=-2>Extended ASCII</font></font></td>

<td VALIGN=TOP WIDTH="20%"><font face="Courier New"><font size=-2>(LinesOverwrite</font></font></td>

<td VALIGN=TOP WIDTH="30%"><b><font face="Courier New"><font size=-2>&lt;ws><sub>'opaque'|'merge'|'transparent</sub></font></font></b></td>

<td VALIGN=TOP WIDTH="31%"><font face="Arial"><font size=-2>-</font></font></td>
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<p><font face="Arial Black"><font size=-1>Details</font></font>
<ul>Currently <b>Merge Control</b> is supported as an enumerated value.
Three states are supported: "lines overwrite", "lines merge" and "transparent."
<p>Merge control is set only in the WHIP! data. If set, <b>Merge
Control</b> state applies to the drawable that follows it. In otherwords,
<b>Merge
Control</b> is supported as a rendition attribute for drawables.
<p>Only Extended&nbsp; ASCII is supported,&nbsp; there is no binary or
extended binary support.
<font face="Arial Black"><font size=-1>Use Cases</font></font>
<blockquote>Draw a few black lines. Then draw a light gray solid over them.
If the state is "lines overwrite", then the light gray solid will obscure
the black lines in a gray-scale plot. If&nbsp; the state is "lines merge,"
the black lines will be visible.</blockquote>

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